jackc/pgx · error

cannot scan empty string into %T

Error message

cannot scan empty string into %T

What it means

Text bool scan plan got a zero-length, non-NULL source. An empty string cannot be interpreted as a PostgreSQL boolean, unlike valid representations like 't', 'true', '1'.

Solutions

1. Store/emit a real boolean representation ('t','true','yes','1','f','false','no','0')
2. Treat empty strings as NULL before scanning, if that matches your data
3. Fix upstream data production that created empty boolean text

When it happens

Trigger: Thrown at pgtype/bool.go:273 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of jackc/pgx@ec1a0befd2 (2026-08-04). Data as JSON: /api/errors/06b9f48c51c7d67f. Report an issue: GitHub.

Appendix: source

Thrown at pgtype/bool.go:273

	p, ok := (dst).(*bool)
	if !ok {
		return ErrScanTargetTypeChanged
	}

	*p = src[0] == 1

	return nil
}

type scanPlanTextAnyToBool struct{}

func (scanPlanTextAnyToBool) Scan(src []byte, dst any) error {
	if src == nil {
		return fmt.Errorf("cannot scan NULL into %T", dst)
	}

	if len(src) == 0 {
		return fmt.Errorf("cannot scan empty string into %T", dst)
	}

	p, ok := (dst).(*bool)
	if !ok {
		return ErrScanTargetTypeChanged
	}

	v, err := planTextToBool(src)
	if err != nil {
		return err
	}

	*p = v

	return nil
}

type scanPlanBinaryBoolToBoolScanner struct{}

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